[IPV6]: Add RFC4214 support

This patch includes support for the Intra-Site Automatic Tunnel
Addressing Protocol (ISATAP) per RFC4214. It uses the SIT
module, and is configured using extensions to the "iproute2"
utility. The diffs are specific to the Linux 2.6.24-rc2 kernel
distribution.

This version includes the diff for ./include/linux/if.h which was
missing in the v2.4 submission and is needed to make the
patch compile. The patch has been installed, compiled and
tested in a clean 2.6.24-rc2 kernel build area.

Signed-off-by: Fred L. Templin <fred.l.templin@boeing.com>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 0 deletions

diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index bccc2feb99da..c56827da0dee 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -17,6 +17,7 @@
 
 #define IPV6_MAX_ADDRESSES              16
 
+#include <linux/in.h>
 #include <linux/in6.h>
 
 struct prefix_info {
@@ -249,6 +250,24 @@ static inline int ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
                 addr->s6_addr32[3] == htonl(0x00000002));
 }
 
+static inline int ipv6_isatap_eui64(u8 *eui, __be32 addr)
+{
+        eui[0] = (ZERONET(addr) || PRIVATE_10(addr) || LOOPBACK(addr) ||
+                  LINKLOCAL_169(addr) || PRIVATE_172(addr) || TEST_192(addr) ||
+                  ANYCAST_6TO4(addr) || PRIVATE_192(addr) || TEST_198(addr) ||
+                  MULTICAST(addr) || BADCLASS(addr)) ? 0x00 : 0x02;
+        eui[1] = 0;
+        eui[2] = 0x5E;
+        eui[3] = 0xFE;
+        memcpy (eui+4, &addr, 4);
+        return 0;
+}
+
+static inline int ipv6_addr_is_isatap(const struct in6_addr *addr)
+{
+        return ((addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE));
+}
+
 #ifdef CONFIG_PROC_FS
 extern int if6_proc_init(void);
 extern void if6_proc_exit(void);